http://api.tweetmeme.com/imagebutton.gif?url=http://sports.espn.go.com/nba/news/story?id=6613244&campaign=rss&source=NBAHeadlines (http://api.tweetmeme.com/share?url=http://sports.espn.go.com/nba/news/story?id=6613244&campaign=rss&source=NBAHeadlines&service=bit.ly&source=espn)NBA Commissioner David Stern says the sale of the Detroit Pistons to California investor Tom Gores has been approved by the league.